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them. The Royal Agricultural Society of England, per- 

 ceiving the importance of this subject, has recently offered 

 a prize of £50 for an essay on the indications which are 

 practical guides ; for, say they, " Many attempts having been 

 " made to explain the productiveness of the soil by chemical 



or physical causes without any decided result, it appears 

 " desirable to assist the researches of natural philosophers, 

 ** by making them acquainted with those obvious signs, 



whether of colour, consistence, or vegetation, by which 



farmers and surveyors are enabled to give at once a 

 " practical opinion upon the probable nature of land which 

 " they inspect." 



I do not, however, purpose to confine these observations to 

 the obvious signs named by the Royal Society, because there 

 is no single sign which is infallible under all circumstances. 

 Some are more to be relied upon than others ; while a 

 Chemical or Geological sign of easy application, becomes as 

 much a practical sign as either that of colour, consistence, 

 or vegetation. 



1. Respecting the Colour of soils, which is variable on all 

 descriptions of land. The darker soils, rich in vegetable 

 matter, are usually esteemed good ; yet some of those, 

 inclining to be peaty, although of this colour, are infertile. 

 Sandy soils, which after rain remain of a light colour, are in 

 general accounted unproductive ; yet some of the Wold 

 soils, which contain many flints or white pebbles, are of this 

 colour after rain, and, nevertheless, are of fair quality. Again, 

 at Bentley and Arksey, near Doncaster, there exists excellent 

 land of a yellow colour, while there is other there equally 

 good of a dark blue colour. The productive soils of the 

 Green Sand below the Chalk are green, while those of the 

 New Red Sandstone are red. Therefore colour alone, 

 however valuable, cannot be relied upon as a criterion of the 

 quality of land. 



